Booking will open and almost certainly close on Monday for one of the most keenly awaited reunions in showbusiness history: the return of Monty Python's Flying Circus.

Tickets for the show, at London's O2 Arena, will be priced between £27 and £90, or "£300 less than the Rolling Stones" as they put it. "If you don't mind paying five or six times the cover price, give me a buzz," said Terry Gilliam, with a pantomime villain wink.

There will be no silly walks, because John Cleese has said his artificial hip and knee aren't up to it, but there will be singers and dancers, parrot jokes – "what was it now … Norwegian?" Michael Palin said, gazing up for inspiration – and Gilliam animations. Lots of Gilliam animations, he said firmly.

"There will be a little comedy, some pathos, music, and a tiny bit of ancient sex," Eric Idle, who will direct, promised.

Apart from an insistence that the purpose of the reunion is to pay off Terry Jones's mortgage, they said they were getting together again – 40 years after the last UK stage appearance and 33 years after the Hollywood Bowl, the last appearance by the whole team before Graham Chapman's death in 1989 – because they still found the material funny.

"We may not like one another but put us together in a room and we laugh a lot," said Cleese.

The press launch was artfully anarchic. The five walked on stage, a fashionable 20 minutes late, all talking simultaneously, and Palin plugging the next instalment of his travel diaries until called to order by the MC, Warwick Davis. They then sat in the wrong places, insisted on answering one another's questions, and groaned when Davis opened a gold envelope to announce that, thanks to calling in Sepp Blatter to help process all the cities bidding to host the show, it would be in Qatar.

He opened a second envelope and announced that the winner was Meryl Streep, before conceding that, since London had put in "the second highest bribe – er, bid", it would, after all, get the honour.

A wildly cosmopolitan media scrum packed into the Playhouse theatre, including crews from Australia – the show's not going there, Cleese said firmly, "the problem with Australia is there are planets closer" – the US, Japan, and the home of the poorly parrot, Norway.

The first question, to Palin's rapture, was asked by a Spanish radio reporter. "Nobody expects the Spanish inquisition," he murmured in delight.

The surviving Pythons now have a collective age of 357, and the working title for the show is "One down, five to go". Medical attendants will be in the wings, they explained, and the alternate title is "Two down, four to go".